ELS Messages for Transmission Control Protocol (TCP)


TCP.001

Level:
UI-ERROR
Short Syntax:
TCP.001 pkt cksum fld pkt = tcp_checksum calc = tcp_checksum
Long Syntax:
TCP.001 packet checksum failed received packet checksum is tcp_checksum and calculated checksum is tcp_checksum
Description:
Checksum failed because received packet checksum is not equal to the calculated checksum

TCP.002

Level:
UI-ERROR
Short Syntax:
TCP.002 rcvd pkt source_ip_address -> destination_ip_address dst prt tcp_port no cnn
Long Syntax:
TCP.002 received packet source_ip_address -> destination_ip_address with destination port tcp_port has no tcp connection
Description:
TCP has received a packet with an invalid tcp port number.

TCP.003

Level:
C-INFO
Short Syntax:
TCP.003 Act opn sccfl dst prt tcp_port
Long Syntax:
TCP.003 TCP Active open successful for port number tcp_port
Description:
Active open was successful and we are notifying application of the open.

TCP.004

Level:
UI-ERROR
Short Syntax:
TCP.004 rcvd invld SYN in wndw source_ip_address -> destination_ip_address dst prt tcp_port kill cnn
Long Syntax:
TCP.004 received invalid SYN packet source_ip_address -> destination_ip_address with destination port tcp_port , kill connection
Description:
TCP has received an illegal SYN packet, so kill the connection.

TCP.005

Level:
UI-ERROR
Short Syntax:
TCP.005 rcvd old SYN source_ip_address -> destination_ip_address dst prt tcp_port snd ACK
Long Syntax:
TCP.005 received old duplicate SYN packet source_ip_address -> destination_ip_address with destination port tcp_port , send ACK packet in response
Description:
TCP has received an old duplicate SYN, so send ACK with received sequence number; this forces the other side to do a RST.

TCP.006

Level:
UI-ERROR
Short Syntax:
TCP.006 rcvd out of wndow seg source_ip_address -> destination_ip_address dst prt tcp_port snd ACK
Long Syntax:
TCP.006 received an out of window segment source_ip_address -> destination_ip_address with destination port tcp_port , send a valid ACK
Description:
TCP has received an out of window segment; send ACK in response.

TCP.007

Level:
UI-ERROR
Short Syntax:
TCP.007 drp seg source_ip_address -> destination_ip_address dst prt tcp_port rsn reject_code snd ACK
Long Syntax:
TCP.007 dropped segment source_ip_address -> destination_ip_address with destination port tcp_port , reason reject_code , send a valid ACK in response
Description:
TCP has rejected a segment. Reject codes are as follows: Reject codes: 1 - Seg len = 0, Rcv win > 0, seqnum < tcb_ack or seqnum >= winend 2 - Seg len = 0, Rcv win = 0, seqnum != tcb_ack 3 - Seg len > 0, Rcv win > 0, inend < tcb_ack or seqnum >= winend 4 - Seg len > 0, Rcv win = 0. Note: we only ACK if the segment received was a non RST segment.

TCP.008

Level:
UI-ERROR
Short Syntax:
TCP.008 rcvd old seg dst prt tcp_port seq num seq_num snd ACK
Long Syntax:
TCP.008 received old duplicate packet with destination port tcp_port , sequence number seq_num , send ACK in response
Description:
TCP has received an old segment that has already been consumed by the application, so send ACK in response.

TCP.009

Level:
C-INFO
Short Syntax:
TCP.009 state LISTEN: rcvd RST dst prt tcp_port seq num seq_num
Long Syntax:
TCP.009 while in LISTEN state, received RST with destination port tcp_port , sequence number seq_num ; drop segment
Description:
TCP has received a RST while in LISTEN state; just ignore packet.

TCP.010

Level:
C-INFO
Short Syntax:
TCP.010 state SYN_RCVD|SYN_SNT: rcvd RST dst prt tcp_port seq num seq_num , rtrn to LISTEN
Long Syntax:
TCP.010 while in SYN_RECEIVED or SYN_SENT states, received RST with destination port tcp_port , sequence number seq_num ; drop segment and return to LISTEN state
Description:
TCP has received a RST while in SYN_RECEIVED or SYN_SENT states; drop packet and return to LISTEN state.

TCP.011

Level:
C-INFO
Short Syntax:
TCP.011 rcvd RST dst prt tcp_port seq num seq_num , abort
Long Syntax:
TCP.011 received RST with destination port tcp_port , sequence number seq_num ; drop segment and abort connection
Description:
TCP has received a RST; abort connection.

TCP.012

Level:
UI-ERROR
Short Syntax:
TCP.012 drop seg dst prt tcp_port seq num seq_num no ACK present
Long Syntax:
TCP.012 drop segment with destination port tcp_port , sequence number seq_num because no ACK is present
Description:
TCP has stopped processing the packet because there is no ACK present in the packet.

TCP.013

Level:
UI-ERROR
Short Syntax:
TCP.013 drop seg dst prt tcp_port seq num seq_num ack num ack_num rcv invld ACK
Long Syntax:
TCP.013 drop segment with destination port tcp_port , sequence number seq_num , acknowledge number ack_num , received invalid ACK
Description:
Stop processing the segment because it contains acknowledgement for data not yet sent.

TCP.014

Level:
C-INFO
Short Syntax:
TCP.014 state ESTAB: rcvd FIN dst prt tcp_port seq num seq_num
Long Syntax:
TCP.014 while in ESTABLISHED state, received FIN with destination port tcp_port , sequence number seq_num
Description:
TCP has received a FIN while in ESTABLISHED state; when all data has been received, send FIN|ACK.

TCP.015

Level:
C-INFO
Short Syntax:
TCP.015 rcvd PSH dst prt tcp_port seq num seq_num
Long Syntax:
TCP.015 received a segment with the PSH bit set with destination port tcp_port , sequence number seq_num
Description:
TCP has received a segment with PSH bit set.

TCP.016

Level:
C-INFO
Short Syntax:
TCP.016 state SYNRCVD: rcvd vld seg dst prt tcp_port seq num seq_num , enter ESTAB
Long Syntax:
TCP.016 while in SYNRCVD state, received valid segment with destination port tcp_port , sequence number seq_num , so enter ESTABLISHED state
Description:
TCP has received a valid segment while in SYNRCVD state; enter ESTABLISHED state and notify application of the open.

TCP.017

Level:
UI-ERROR
Short Syntax:
TCP.017 rcvd FIN while in LISTEN dst prt tcp_port seq num seq_num , snd RST
Long Syntax:
TCP.017 received FIN segment while in the LISTEN state, destination port tcp_port , sequence number seq_num , snd RST
Description:
TCP has received a FIN while in the LISTEN state, so we send RST to the other side.

TCP.018

Level:
C-INFO
Short Syntax:
TCP.018 rcvd out of order seg dst prt tcp_port seq num seq_num , add hole at end seq_num to seq_num
Long Syntax:
TCP.018 received an out of order segment with destination port tcp_port , sequence number seq_num ; hole created at end of receive buffer seq num seq_num to seq_num
Description:
TCP has received an out of order packet; this creates a hole in the receive buffer.

TCP.019

Level:
C-INFO
Short Syntax:
TCP.019 rcvd out of order seg dst prt tcp_port seq num seq_num , add hole at end seq_num to seq_num
Long Syntax:
TCP.019 received an out of order segment with destination port tcp_port , sequence number seq_num ; hole created at end of receive buffer seq num seq_num to seq_num
Description:
TCP has received an out of order packet; this creates a hole in the receive buffer.

TCP.020

Level:
C-INFO
Short Syntax:
TCP.020 rcvd seg dst prt tcp_port seq num seq_num , prtally fill bgnng hole seq_num to seq_num
Long Syntax:
TCP.020 received segment with destination port tcp_port , sequence number seq_num ; partially fills the beginning of a hole seq_num to seq_num
Description:
TCP has received a packet that partially fills the beginning of a hole.

TCP.021

Level:
C-INFO
Short Syntax:
TCP.021 rcvd seg dst prt tcp_port seq num seq_num , prtally fill end hole seq_num to seq_num
Long Syntax:
TCP.021 received segment with destination port tcp_port , sequence number seq_num ; partially fills the end of a hole seq_num to seq_num
Description:
TCP has received a packet that partially fills the end of a hole.

TCP.022

Level:
C-INFO
Short Syntax:
TCP.022 rcvd seg dst prt tcp_port seq num seq_num , rmv hole seq_num to seq_num
Long Syntax:
TCP.022 received segment with destination port tcp_port , sequence number seq_num ; completely fills a hole, removing hole seq_num to seq_num
Description:
TCP has received a packet that completely fills a hole.

TCP.023

Level:
UI-ERROR
Short Syntax:
TCP.023 drp seg dst prt tcp_port seq num seq_num , too big for rcv buff
Long Syntax:
TCP.023 drop segment with destination port tcp_port , sequence number seq_num ; segment too big for receive buffer
Description:
TCP has received a packet that is too big to fit into the remaining space in the receive buffer.

TCP.024

Level:
UI-ERROR
Short Syntax:
TCP.024 prcss FIN in invld state
Long Syntax:
TCP.024 process a received FIN; current state is not SYNRCVD|ESTAB, so do nothing
Description:
TCP processing FIN while not in SYNRCVD|ESTAB state.

TCP.025

Level:
C-INFO
Short Syntax:
TCP.025 prcss FIN in ESTAB|SYNRCVD state frgn hst ip_address lcl hst ip_address dprt dst_port sprt src_port
Long Syntax:
TCP.025 process a received FIN; current state is SYNRCVD|ESTAB, foreign host ip_address local host ip_address destination port dst_port source port src_port
Description:
TCP processing FIN while in SYNRCVD|ESTAB state.

TCP.026

Level:
C-INFO
Short Syntax:
TCP.026 app rcv tmout
Long Syntax:
TCP.026 application posted receive timeout has fired
Description:
Application posts a read specifying a timeout value. If not all the requested data has been received within a timeout period, a timer fires, and whatever is in the receive buffer is given to the application.

TCP.027

Level:
UI-ERROR
Short Syntax:
TCP.027 frgn prt illgl close of wndw frgn hst ip_address lcl hst ip_address dprt dst_port sprt src_port
Long Syntax:
TCP.027 foreign port closed the advertised window illegally foreign host ip_address local host ip_address destination port dst_port source port src_port
Description:
The other side has been deaf and mute, and the the foreign window seems to have been closed illegally; send a RST.

TCP.028

Level:
C-INFO
Short Syntax:
TCP.028 state trnstn to SYNRCVD
Long Syntax:
TCP.028 state of TCP connection transitioned to SYN-RECEIVED state
Description:
State of the connection has transitioned to SYN-RECEIVED state as a result of either an active open or a passive open.

TCP.029

Level:
C-INFO
Short Syntax:
TCP.029 state trnstn to ESTAB
Long Syntax:
TCP.029 state of TCP connection transitioned to ESTABLISHED state
Description:
State of the connection has transitioned to ESTABLISHED state as a result of either an active open or a passive open.

TCP.030

Level:
P-TRACE
Short Syntax:
TCP.030 rcvd TCP pkt source_ip_address -> destination_ip_address dst prt tcp_port
Long Syntax:
TCP.030 received packet source_ip_address -> destination_ip_address with destination port tcp_port
Description:
TCP has received a packet.

TCP.031

Level:
P-TRACE
Short Syntax:
TCP.031 seq num seq_num to seq_num given to app.
Long Syntax:
TCP.031 data with sequence number seq_num through to seq_num given to application
Description:
Valid data in receive buffer has been handed to the application for further processing.

TCP.032

Level:
C-INFO
Short Syntax:
TCP.032 excssv num rtries
Long Syntax:
TCP.032 excessive number of retries has occurred
Description:
We have retransmitted a frame an excessive number of times. If the application has closed the connection already, just abort. Else, notify the application that there is a problem.

TCP.033

Level:
P-TRACE
Short Syntax:
TCP.033 snd ctrl seg seq num seq_num ack num ack_num wndw window
Long Syntax:
TCP.033 send control segment with sequence number seq_num and acknowledge number ack_num window window
Description:
Send a control segment to either ack a segment or send special control segments like FIN or RST.

TCP.034

Level:
C-INFO
Short Syntax:
TCP.034 rxmt seq num seq_num to seq_num
Long Syntax:
TCP.034 retransmit data with sequence number seq_num through to seq_num
Description:
We have failed to receive a valid ACK for transmitted data, so retransmit the data.

TCP.035

Level:
P-TRACE
Short Syntax:
TCP.035 xmt seq num seq_num to seq_num
Long Syntax:
TCP.035 transmit data with sequence number seq_num through to seq_num
Description:
Transmit data.

TCP.036

Level:
UI-ERROR
Short Syntax:
TCP.036 illgl optn rcvd in SYN seg
Long Syntax:
TCP.036 illegal option received in SYN segment
Description:
An unsupported option is present in the options field of a SYN packet.

TCP.037

Level:
C-INFO
Short Syntax:
TCP.037 zero wndw probe seq num seq_num
Long Syntax:
TCP.037 zero window probe segment with sequence number seq_num sent
Description:
The other side has advertised a zero window in the last segment received, so we have to send a zero window probe.

TCP.038

Level:
UI-ERROR
Short Syntax:
TCP.038 rjct seg dst prt tcp_port seq num seq_num bad ACK in SYNRCVD, snd RST
Long Syntax:
TCP.038 reject segment with destination port tcp_port and sequence number seq_num , bad ACK in segment while in SYNRCVD state
Description:
Reject the segment, and send a RST to the other side for receiving a segment with the incorrect acknowledgement while in the SYNRCVD state. Until a correct acknowledgement is received, we cannot progress into the ESTABLISHED state.

TCP.039

Level:
UI-ERROR
Short Syntax:
TCP.039 rcvd ACK seg with dst prt tcp_port seq num seq_num in LISTEN, snd RST
Long Syntax:
TCP.039 received ACK segment with destination port tcp_port , sequence number seq_num while in the LISTEN state, send RST
Description:
TCP has received an ACK while in the LISTEN state; this does not make any sense because we have not yet sent any data, so nothing should be ACKed. As a result, we send a RST.

TCP.040

Level:
UI-ERROR
Short Syntax:
TCP.040 TCP snd rst to hst source_ip_address
Long Syntax:
TCP.040 TCP sending RESET to host source_ip_address
Description:
TCP is sending a RESET segment to the other side.

TCP.041

Level:
C-INFO
Short Syntax:
TCP.041 TCP cnn clsd frgn hst foreign_ip_address lcl hst local_ip_address
Long Syntax:
TCP.041 TCP connection closed, foreign host foreign_ip_address , local hst local_ip_address
Description:
TCP connection is closed - notifying the application.

TCP.042

Level:
C-INFO
Short Syntax:
TCP.042 Frng TCB for frgn hst foreign_ip_address lcl hst local_ip_address
Long Syntax:
TCP.042 Freeing TCB block for connection between foreign_ip_address and local_ip_address
Description:
Freeing the TCB block associated with the TCP connection that has closed.

TCP.043

Level:
C-INFO
Short Syntax:
TCP.043 Frng TCB for frgn hst foreign_ip_address lcl hst local_ip_address
Long Syntax:
TCP.043 Freeing TCB block for connection between foreign_ip_address and local_ip_address
Description:
Freeing the TCB block associated with the TCP connection that has closed.

TCP.044

Level:
C-INFO
Short Syntax:
TCP.044 Idle tmr fires frgn hst foreign_ip_address lcl hst local_ip_address
Long Syntax:
TCP.044 Idle timer fires for connection between foreign_ip_address and local_ip_address
Description:
Idle timer fires for TCP connection.

TCP.045

Level:
C-INFO
Short Syntax:
TCP.045 Rxmt tmr fires frgn hst foreign_ip_address lcl hst local_ip_address
Long Syntax:
TCP.045 Retransmit timer fires for connection between foreign_ip_address and local_ip_address
Description:
Retransmit timer fires for TCP connection.

TCP.046

Level:
C-INFO
Short Syntax:
TCP.046 State trnstn frm ESTAB to FINWAIT source_ip_address -> destination_ip_address dst prt tcp_src_port src prt tcp_dst_port
Long Syntax:
TCP.046 State transitioned from ESTABLISHED to FINWAIT source_ip_address -> destination_ip_address dst prt tcp_src_port src prt tcp_dst_port
Description:
State of tcp connection has transitioned from ESTABLISHED to FINWAIT - send FIN, and now waiting for FIN-ACK to arrive.

TCP.047

Level:
C-INFO
Short Syntax:
TCP.047 State trnstn to CLOSED source_ip_address -> destination_ip_address dst prt tcp_src_port src prt tcp_dst_port
Long Syntax:
TCP.047 State transitioned to CLOSED source_ip_address -> destination_ip_address dst prt tcp_src_port src prt tcp_dst_port
Description:
State of tcp connection has transitioned to CLOSED.

TCP.048

Level:
C-INFO
Short Syntax:
TCP.048 Rcvd data after CLOSE issued and zero wndw, snd RST source_ip_address -> destination_ip_address dst prt tcp_src_port src prt tcp_dst_port
Long Syntax:
TCP.048 Received data after CLOSE was issued, and window is zero, send RESET source_ip_address -> destination_ip_address dst prt tcp_src_port src prt tcp_dst_port
Description:
TCP connection is CLOSING due to application requesting a CLOSE. After the window shrinks to zero, discard any packets received. This is based on the half-duplex TCP close sequence.

TCP.049

Level:
C-INFO
Short Syntax:
TCP.049 Rcvd NACK
Long Syntax:
TCP.049 Received NACK
Description:
The other side has send an old ACK with zero data length - we treat this as a NACK.

TCP.050

Level:
C-INFO
Short Syntax:
TCP.050 Rcvd ACK for Keep Alive
Long Syntax:
TCP.050 Received Acknowledge for the keep alive packet sent
Description:
The other side has acknowledged the keep alive packet. The keep alive packet is sent if keep alive is enabled on this tcp connection, and the connection has been idle.

TCP.051

Level:
C-INFO
Short Syntax:
TCP.051 Lcl wndw zero
Long Syntax:
TCP.051 Local window zero
Description:
The local window advertised is zero. The application is not draining the tcp receive buffer fast enough.

TCP.052

Level:
C-INFO
Short Syntax:
TCP.052 snd FIN seq seq_num , ack ack_num
Long Syntax:
TCP.052 send FIN sequence number seq_num , acknowledge number ack_num
Description:
The TCP connection is closing, and we sent a FIN.

TCP.053

Level:
C-INFO
Short Syntax:
TCP.053 get buf fld - cannot snd pkt
Long Syntax:
TCP.053 get buf failed - cannot send packet
Description:
The router is running out of iorbs, getbuf failed, so we cannot send a packet.

TCP.054

Level:
C-INFO
Short Syntax:
TCP.054 xmit buf too large ( requested_amount lipped to clipped_amount
Long Syntax:
TCP.054 transmit buffer too large for listen/open ( requested_amount ), clipped to ( clipped_amount )
Description:
The transmit buffer size requested for a TCP connection is too large to be allocated by the system. TCP has selected in its place the largest chunk size available in the system.

TCP.055

Level:
C-INFO
Short Syntax:
TCP.055 recv buf too large ( requested_amount lipped to clipped_amount
Long Syntax:
TCP.055 receive buffer too large for listen/open ( requested_amount ), clipped to ( clipped_amount )
Description:
The receive buffer size requested for a TCP connection is too large to be allocated by the system. TCP has selected in its place the largest chunk size available in the system.